Baseline characteristics of included patients stratified by individual cohort
| Derivation cohort (n=703) | Validation cohort 1 (n=462) | Validation cohort 2 (n=191) | Validation cohort 3 (n=806) | |
|---|---|---|---|---|
| Age in years, mean (SD) | 58.6 (14.3) | 63.8 (15.6) | 57.0 (14.7) | 57.9 (13.1) |
| Men (%) | 430 (61.2) | 270 (58.4) | 122 (63.9) | 482 (59.8) |
| Previous angina (%) | 221 (31.4) | 185 (40.0) | 54 (28.3) | 210 (26.1) |
| Previous myocardial infarction (%) | 167 (23.8) | 138 (29.9) | 54 (28.3) | 177 (22.0) |
| Hypertension (%) | 343 (48.8) | 197 (42.6) | 76 (39.8) | 455 (56.5) |
| Hyperlipidaemia (%) | 339 (48.2) | 186 (40.3) | 62 (32.5) | 534 (66.3) |
| Diabetes mellitus (%) | 125 (17.8) | 80 (17.3) | 27 (14.1) | 137 (17.0) |
| Current smoking (%) | 216 (30.7) | 96 (20.8) | 52 (27.2) | 192 (23.8) |
| Previous coronary intervention (%) | 140 (19.9) | 101 (21.9) | 43 (22.5) | 158 (19.6) |
| Time from symptom onset to arrival in the ED (median, IQR) | 2.5 (1.2–5.8) | 3.4 (1.7–9.1) | 3.2 (1.4–5.6) | 2.3 (0.4–4.1) |
| Outcomes | ||||
| Number with AMI (%) | 130 (18.5) | 79 (17.1) | 29 (15.2) | 64 (7.9) |
| Number with ACS (%) | 151 (21.5) | 94 (20.3) | 37 (19.4) | 81 (10.0) |
| Number with death at 30 days (%) | 5 (0.7) | 6 (1.3) | 3 (1.6) | 1 (0.1) |
| Number with incident AMI at 30 days (%) | 2 (0.3) | 12 (2.6) | 0 (0.0) | 0 (0.0) |
| Number with coronary revascularisation at 30 days (%) | 99 (14.1) | 46 (10.0) | 20 (10.5) | 55 (6.8) |
| Number with coronary stenosis at 30 days (%) | 111 (15.8) | 55 (11.9) | 30 (15.7) | 91 (11.3) |
| Predictors in the T-MACS model | ||||
| Acute ECG ischaemia (%) | 196 (27.9) | 105 (22.7) | 49 (25.7) | 0 (0.0) |
| Worsening angina (%) | 108 (15.4) | 94 (20.3) | 25 (13.1) | 125 (15.5) |
| Patient reports vomiting in association with the chest pain (%) | 47 (6.7) | 33 (7.1) | 10 (5.2) | 35 (4.3) |
| Sweating observed (%) | 82 (11.7) | 25 (5.4) | 13 (6.8) | 27 (3.3) |
| Systolic BP <100 mm Hg (%) | 23 (3.3) | 17 (3.7) | 6 (3.1) | 27 (3.3) |
| hs-cTnT, median (IQR) | 7.6 (<3–17.5) | 9.8 (5.3–22.9) | 4.0 (<3–16.0) | 7.2 (4.6–11.9) |
| hs-cTnT >14 ng/L (%) | 212 (30.2) | 181 (39.2) | 46 (24.1) | 159 (19.7) |
| Pain radiating to right arm or shoulder (%) | 69 (9.8) | 59 (12.8) | 24 (12.6) | 93 (11.5) |
ACS, acute coronary syndromes; AMI, acute myocardial infarction; hs-cTnT, high sensitivity cardiac troponin T; T-MACS, Troponin-only Manchester Acute Coronary Syndromes.